Playing a sound file remotely?

I work in a collections place, part of the way they do business is by requiring a general manager to hop on calls when debtors get to a certain point in a conversation. At the moment, the collectors are basically shouting for a manager to come to their desks. What I'm looking to do is to set up a form that will play a wav file requesting the general manager from a dedicated machine on the LAN. Basically a paging system run via PC.We are all using Windows 7.

So basically, what's the best way to have a button click fire a command to a remote machine to play a wav (or mp3) file?